Pipe covering



Patented Mar. 6, 1928.

UNITED STATES PATENT OFFICE.

WILLIAM R. GILLIES, OF CHICAGO, ILLINOIS, ASSIGNOB 'IO UNION ASBESTOS, & BUB- BER COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

PIPE COVERING.

Application filed January 25, 1926. Serial 110,813,461.

The present invention relates to pipe coverings, and more particularly to that type of heat insulating pipe covering adapted to be folded or wrapped circumferentially about the pipe with the lateral edges of the covering meeting in a longitudinal seam.

One of the particular objects of the present invention is to provide a pipe covering of this general type characterized by an improved arrangement of reinforced or stilfened edges to provide and maintain an overlapped joint between the lateral edges of the covering along the entire length of the pipe.

The further object is to provide apipe covering of this type in which the main insulating filler and the stiffened edges for overlap ing are all enclosed in a single casing or s eath.

Another object is to provide a pipe covering in which the casing or'sheath has its woof and warp threads so disposed relative to the length of the covering as to enable the covering to adapt itself more readily to bends in the pipe.

' Referring to the accompanying drawing illustrating my invention:

Fig. 1 is a perspective view of one embodiment of my improved pipe covering, the end of the covering being illustrated in section to show the component arts thereof.

Fig. 2 illustrates the app ication of this embodiment of covering toa pipe.

Fig. 3 is a view similar to Fig. 1, of a modified construction, and

' Fig. 4 illustrates the application of this latter embodiment to a pipe The covering comprises a casing of sheath 6 which is preferably formed of a heat insulating and heat resisting material such, for instance, as a textile fabric having woof and war threads of asbestos fibre. The casing or slieath is formed, seamed-or stitched upon itself to form three parallel compartments or pockets, all of which are coextensive with the covering, namely and the lateral pockets 8 and"'9.- Preferably, the edges of the casing orsheath areoverlapped at a point substantially intermediate the width of the covering and are stitched together as' indicated at 11. The lateral oekets 8 and 9 are also preferably formed y stitching together the outer and inner plies of the easin along the hnes 12 and 13.

Disposed ,side y side within the intermediate pocket 7 and extending continuously and longitudinally therethrough is a plurallty of independent strands or ropes 14, each of which is preferably formed of relatlvely soft felted asbestos fibre. Each of the elements 14-44 may consist of felted or twisted fibre, or may consist of a number of. asbestos cords twisted together to form a rope. However while I prefer to fill the pocket 7 with a plurality of asbestos ropes as iereinbefore egrplained a single strip or body of asbestos felt, or an equivalent material, may be insertedin the pocket 7 in accordance with my invention.

The intermediate portion of the covering filled by this heat insulating filler 14.- is of suflicient width substantially to embrace the circumference of the pipe.

Disposed in each of the lateral pockets 8 and 9 and extending continuously and longi-- tudinally therethrough are the stifl'ening elements 16 consisting, in this embodiment, of asbestos fibre boards. These asbestos fibre boards have a certain degree of pliability, but are decidedly stifi'er than the intermediate body portion of the covering to secure and maintain the overla ped' joint. These reinforced boards are re erably of a thickness equal to substantially one-half of the thickness of the intermediate body portion so that the resultant joint will notprgtrude objectionably from the pipe covering.

This covering is folded or lapped about the pipe p circumferentiall as indicated in Fig. 2. When thus place about the pipe one "of the relatively stiff edge portions 16 will be placed on top of the other edge portion in overlapping relation. Thereupon the usual bindin ties 19 of wire or flexible metal strapping Wlll be fastened around the coverin at spaced intervals. The overlapping refittion of the two reinforced edges will providev a snugly fitting overlapping joint 'which will have practically the same heat insulating properties as the intermediate body portion of the covering. This .overlappin joint will also be of substantially the same t ickness as the intermediate body ortion. The stiffness of the reinforced e ges will maintain the overlapped joint'and prevent the edges of the covering from opening up or spreading, particularly in'the intervals between binding ties 19. 'By virtue of this stiffness of the marginal edges tending to maintain the joint the binding ties 19 do not have to be placed as close together as has been heretofore necessary. Where the covering is to be extended around a bend in the pipe the covering may be. so disposed on the pipe as to place the joint on the outside of the curve where the reinforced edge portions will be subjected to endwise tension stresses tending to hold the joint closed.

Pipe coverings of this general type, as'

ordinarily made, are difficult to shape around bends in the pipe without bunching and bulging of the material. I have found that this can be alleviated to a large extent by constructing the sheath with its woof and warp threads or strands on the bias.. That is to say, the sheath or casing has its woof and warp extending diagonally thereof, substantially as indicated in Fig. 1, and when the covering is on the pipe these woof and warp threads will extend diagonally relative to the axis of the pipe. This diagonaldirection ofwoof and warp permits a greater expansion of the material around the outside of the bend and a greater compression of the material around the inside of the bend without bunching or bulging, whereby the covering can be shaped more snugly to the bend.

In the'modification shown in Figs. 3 and 4 the edge reinforcement is obtained by inserting in the lateral pockets 8 and 9 lengths of hemp or manila rope 22. In contradistinction to the relatively soft insulating filler 14, these hemp or manila ropes have considerable tensile strength, are considerably stiffer than the insulating filler, and are not subject to any considerable cross-sectional distortion under the stresses to which they are subjected in the process of forming the overlapped joint. The pockets 8 and 9' may be formed by single lines of stitching l2 and 13 as previously described; or secondary-lines of stitching 23 and 24 may be spaced outwardly from the first lines of stitchin to provide intervening web portions 0 fabric 25 of a width substantially equal to the width of the reinforced edges 8 and 9. The heat insulating filler is preferably extended out in relatively thin plies 26 between the upper and lower plies of the sheath in these intervening web portions to pad these Web portions.

The ed es when thus reinforced by the ropes 22 orm beads having-an interlocking action in -.the lapped joint. That is to say, when the covering is folded or lapped about the pipe as shown in Fig. 4 each beaded edge is forced down into the intervening web portion 25 of the other edge, whereby both beaded edges overlap and interlock with each other. Because of the greater stiffness of the ibpes in these beaded edges this interlocking relation of the edges will be maintained over long spans of the pipe. This seam extendinglongitudinally thereof, comprising a fabric casingfilled with a relatively pliable heat insulating material across the greatest portion of its width, and marginal portions of relatively stiffer asbestos board along the lateral edges of said casing, said marginal portions being overlapped in a seam extending longitudinally of the pipe.

2. A pipe covering adapted to be folded circumferentially around a pipe with its seam extending longitudinally thereof, comprising a fabric sheatlr stitched longitudinally upon itself to afford an elongated central pocket of "considerable area in transverse cross section and lateral pockets of lesser transverse cross sectional area which are co-extensive with said central pocket, said central pocket containing a filler in the form of a relatively pliable heat insulating material, each of said lateral pockets containing a relatively stiffer asbestos board to reinforce the edges of the sheath, said reinforced edges being overlapped in a seam extending substantially longitudinally of the pipe.

3. A fpipe covering adapted to be wrapped circum rentially around the pipe with its seam extending longitudinally thereof, comprising a body portion of heat insulating material, reinforced edge portions of relatively stiffer asbestos board and a fabric sheath enclosing said body portion and said reinforced edge portions, said reinforced edge portions being overlapped in a seam extending longitudinally of the pipe.

4. A heat insulating pipe covering adapted to be wrapped circumferentially.

circumferentially around the pipe with its seam extending longitudinally thereof, comprising a fabric sheath filled across the greater portion of its widthwith a relatively pliable heat insulating material, and a reinforcing insert of asbestos board in one edge of said sheath adapted to be overlapped with the other edge of the sheath in a seam extending Substantially longitudinally of the pipe.

6. A pipe covering adapted to be folded circumferentially around the pipe with its seam extending longitudinally thereof, comprising a fabric sheath, a heat insulating filler filling the greater portion of said sheath, and asbestos fibre boards inserted in the lateral edges of said sheath, said asbestos fibre boards being overlapped in a seam extending substantially longitudinally of the pipe.

7. A pipe covering comprising a fabric sheath, a heat insulating filler insaid sheath across the greater portion of its width, and asbestos fibre boards in said sheath along its marginal edges for reinforcing said edges.

8. A pipe covering comprising a tube of heat insulating fabric stitched longitudinally upon itself to afford an elongated central pocket of considerable area in transverse cross section and lateral pockets of lesser cross sectional area, said central pocket containing a relatively pliable heat insulating filler, and each of said lateral pockets containing a length of asbestos fibre board.

9. A pipe covering adapted to be Wrapped circumferentially around the pipe with its seam extending. longitudinally thereof, comprising a fabric sheath, a relatively pliable heat insulating filler in said sheath across the greater portion of its width, and

a reinforcmg strand of relatively stiffer asbestos board in one edge of said sheath to stiffen and reinforce the margin thereof, said stiffened marginal portion being engaged with the other marginal edge of said sheath in a lapped joint extending longitudinally of the pipe.

10. A pipe covering adapted to be folded circumferentially around the pipe with its lateral edges meeting in a seam extending longitudinally of the pipe comprising a fabric sheath, a heat insulating filler filling thegreater portion of said sheath, and rein-- forcing means comprising asbestos board 1n one edge of said sheath for stiffening the edge thereof, said sheath having its woof .and warp extendingdiagonally thereof to facilitate conforming the covering t0 curves in the pipe.

In witness whereof, I hereunto subscribe my name this 18th day of January, 1926. WILLIAM R. GILLIES. 

